Silver halide light-sensitive material containing a heterocyclic thione and a polyalkylene oxide

ABSTRACT

A silver halide light-sensitive material which contains at least one compound selected from the group of compounds represented by the following general formula (I);   and at least one polyalkylene oxide derivative in a silver halide emulsion layer or a layer adjacent thereto. In the above formula, Q represents the atoms necessary to form heterocyclic ring and R represents an alkyl group, an aryl group or a hetero group.

United States Patent 11 1 1111 3,895,948

Shiba et al. 1 July 22, 1975 [541 SILVER HALIDE LIGHT-SENSITIVE 3.294.540 12/1966 Goffe 96/107 ININ A 3.345.175 10/1967 Hayakuwa et al. 96/109 AND A 3.397.987 8/1968 Luckey ct alr 96/1119 3.4316 3/1969 96/1117 POLYALKYLENE OXIDE 3.518.085 6 1970 MlllOfl et 111. 1. 96/1119 75 Inventors: Keisuke Shiba; Seiili Kubodera; 3.692.527 9/1972 V01! 1(bn1g C1211. 96/109 3,708.30} 1/1973 Salesln 96/1117 Reiichi Ohi: Tadao Shishido; Nobuo Yamamoto; Takeo Sakai. all of Kanaguwa Japan Pnmur [:xammer-Won H. Lou1e, .lr1

Atmrmy. Agent. or FirmSughrue, Rothwcll. Minn.

[73] Assignee: Fuji Photo Film Co., Ltd.. Minami 21 d Mucpcuk Ashigara. Japan 22 Filed: Dec. 29, 1972 1571 ABSTRACT A silver halide light-sensitive material which contains [2H Appl' 319315 at least one compound selected from the group of compounds represented by the following general for- [30] Foreign Application Priority Data mula Dec. 28. 1971 Japan .1 47-3037 b s [52] US. Cl .1 96/76 R; 96/95; 96/107; 1 (I) 96/663 [51] Int. Cl. G03c 1/06; 603s 1/28 I [58] Field of Search 96/1117. 109.95.66.31. R

{56] References Cited and at least one Polyalkylene oxide derivative in :1 511 UNITED STATES PATENTS ver halide emulslon layer or a layer ad acent thereto.

1n the above formula, 0 represents the atoms neces- 2.772.164 11/1956 Allen ct 111. 96/109 sary to form heterocyclic ring and R represents an 2.956.876 1 1/|96u Sputh 96/109 3.081.170 3/1963 Ruuch ct 111... 96/109 y group My] group or d hetero gmup' 3.161.521) 12/1964 Ruuch ct a1 96/109 10 Claims, 5 Drawing Figures SILVER HALIDE LIGHT-SENSITIVE MATERIAL CONTAINING A HETEROCYCLIC THIONE AND A POLYALKYLENE OXIDE BACKGROUND OF THE INVENTION l. Field of the Invention The present invention relates to a silver halide lightsensitive material and. more particularly. it relates to a lithographic light-sensitive material which provides an image of a high edge gradient.

2. Description of the Prior Art In a photographic image when a blackened area and non-blackened area are contiguous to each other the ratio of change in optical density versus the distance in a direction at right angles to the tangent is referred to as the edge gradient. In general. the higher the edge gradient the sharper the image. In particular. a lightsensitive material capable of providing an image having a high edge gradient is useful. e.g.. as a lithographic light-sensitive material for use in photographic platemaking processes wherein a dot image is prepared using a glass screen or a contact screen. For the purpose of developing these light-sensitive materials so as to obtain an image with high edge gradient a special de derivative is used has the defect that prolonged development is required in order to obtain high contrast.

In addition. an emulsion containing a polyalkylene oxide derivative requires a long initial development before the start of infectious development, though such an initial development provides. once infectious development starts. high contrast by markedly strengthening the infectious development. Therefore. extremely low contrast gradation obtained in the initial development co-exists with high contrast gradation. which results in insufficient toe-gradation (see FIG. I, curve 11). This results from the fact that the polyalkylene oxide derivative makes the starting point of the infectious development irregular with respect to the individual silver halide grains contained in the emulsion.

To the light-sensitive material in accordance with the present invention can be applied the art of spectral sensitization. Most of sensitizing dyes used for spectral sensitization make the toe-gradation worse. which has also been the case with the aforesaid polyalkylene oxide derivatives. In such cases. even when high contrast is obtained in the half tone image. good dots with sharp edges cannot be obtained by comparatively short time development usually practiced (shorter than 3 minutes) in the case of recording dot images. Good results are obtained with such short time development in the present invention. however.

SUMMARY OF THE INVENTION A primary object of the present invention is. therefore. to provide an emulsion capable of providing high edge gradient with a comparatively short development time.

Another object of the present invention is to provide an emulsion capable of providing dots having good toegradation. i.e.. in the plot of Density vs. Exposure (log E the characteristic curve continues into the region of decreasing exposure with constantly decreasing gradient until at a point the gradient becomes Zero. that is, the curve becomes parallel to coincident with the log E axis. The region. where the curve starts to flatten. is referred to in the art as the toe of the characteristic curve.

A further object of the present invention is to improve the deterioration of toegradation caused by the use of certain sensitizing dyes without a reduction in light sensitivity and while providing a supersensitizing action.

Still a further object of the present invention is to render uniform the size and quality of individual dots in the density region wherein the (lot size is small.

It has been found that the above objects of the pres ent invention can be attained by using a silver halide photographic emulsion containing at least one polyalkylene oxide derivative and at least one compound represented by general formula (I):

wherein 0 represents the atoms necessary to form a hetcrocyclic ring (which heterocyclic ring may be substituted) and R represents an alkyl group. an aryl group or a heterocyclic group.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. is a characteristic curve with optical density (D) on the vertical axis and exposure amount (log E) horizontally.

FIGS. 25 are curves showing the relationship between the distance I L (unit:micron) )-optical density in the edge portion of a dot.

DETAILED DESCRIPTION OF THE INVENTION In the above general formula (I). 0 represents the atoms necessary to complete a heterocyclic ring (which ring may be substituted). such as benzothiazolin-2- thione ring. 6-methyl-benzothiazolin-2-thione ring. 6- ethyl-benzothiazolin-2-thione ring. 6-methoxy-benzothiazolin-Z-thione ring. o chloro-benzothiazolin-2- thione ring, 4,5-tetramethylenethiazolin-Z-thione ring. 4,5-trimethylenethiazolin-Z-thione ring, naphthothiazolin-Z-thione ring. thiazolidin-Z-thione ring (e.g.. thiazolidin2-thione ring. 4-methylthiazolidin2-thione ring. etc.). imidazolin-2-thione ring (eg. l,3-dimethylimidazolin2-thione ring. l.3-diethylimidazolidin-2- thione ring. etc.). selenazolidin-Z-thione ring (e.g.. selenazolidin-Z-thione ring. 4-methylselenazolidin-2- thione ring, etc.). a l.3.4-thiadiazolin-2-thione ring (e.g.. l.3.4-thiadiazolin-2-thione ring, 5-methyl-l.3.4- thiadiazolin-Z-thione ring. S-ethylthio-l .3 .4- thiadiazolin-Z-thione ring. 5-{2-(4-phenyl-5-thio l .3.4- thiadiazolin-2-yl J-mercaptoethylthio} l ,3.4- thiadiazolin-2-thione ring, etc.). l.3.4-selenadiazolin- 2-thione ring (e.g.. l.3.4-selenadiazolin 2-thione ring, 5 ethyl l.3,4-selenadiazolin-Z-thione ring. etc.). 4-

selenazolin-Z-thione ring (e.g.. 4 -selenuzolin-2-thione ring, 4-methyl-4-selenuzolin-2-thi0nc ring, 4-phenyl-4- selenazolin-2-thione ring. etc). l.2dihydropyridin-2- thione ring (cg. l.2 dihydropyridin-Z-thione ring. 6- ethyl-l,Z-dihydropyridin-2-thione ring, etc). benzoxuzolin-IZ-thione ring (e.g.. benzoxazolin-Z-thione ring. 6-ethylbcnz0xazolin-2-thione ring. o-melhoxybenzoxazolin-Z-thione ring. S-methylhenzoxa2olin-2-lhione ring. etc). benzimidazolin-Z-thione ring (cg. 1.3- dimethylbenzimidazolin2-thione ring. 1.3-cli-npropylbenzimidazolin-Z-thione ring. l.3-di-ndecylbcnzimidazolin-Z-thione ring, l.3-di-benzlbenzimiduzoline-Z-thione ring. 5 chl0ro-l.3-dimethylbenzimiduzolin2-thi0ne ring. S methyl-l.3-di-benzylbenzimiduzolin-Z-thione ring, etc). benzoselenuzolin-lthione ring (cg. benzoselenuzolin-Z-thione ring, (rethylbezoselenazolin-Z-thione ring. fi-methoxybenzoselenazolin-Z-thione ring. fi chlorobenzoselenazolin 2-thione ring. etc. l.2-dihydroquinolin-2-thione ring. (e.g.. l.2-dihydroquinolin-2-thione ring, 6-methyl-l .2- dihydroquinolin2-thione ring. 6-chloro-l,2-dihydroquinolin-Z-thione ring. etc), and the like.

The group R includes unsubstituted or hydroxy-. ur vl-, morpholinoor like group-substituted alkyl group having 1-13 carbon atoms. preferably. 1-6 carbon atoms. such as a methyl group. ethyl group. propyl group. hexyl group. decyl group. hydroxyethyl group. benzyl group and a morpholinoethyl group. etc; unsubstituted or alkyL. alkoxy-. halogen-. or the like groupsuhstituted uryl groups. such as a phenyl group. 2- methylphenyl group. 4-methoxyphenyl group, and a 4- chlorophenyl group. etc; heterocyclic ring group. such as Z-pyridyl group. a dipyridyl group and the like.

Specific examples of several preferred compounds used in the present invention include the following 3 compounds:

C S m.p. 90C N 1 CH S m.p. 0 N i C S 74C C S m.p. o

N/ Ase-(@H [5 @iM S 149C s CH 190 c l CH3 3 c s 87C a z S p 30C m.p. 0 n /0 s 8l-82 c S H C 3 /S m.p. H 5 C 3 amp 5 Y S 152 0 9 O H 123 C N\ (3H N 0 N CH 3 (1-38) H C m.p. S S

| C s 625 C s=c CH CH s c s c 2 2 N 3H N-N m.p. 145oC H CS 5 m p a;

.(l 3 S 88C C S '1" 1 4(] 73 C Although the above-illustrated compounds can be N synthesized according to conventionally known processes, synthesis examples of the above compounds are given below.

Synthesis Example 1 (Compounds l-l through l-8) These compounds can be synthesized according to the process described in the Journal of The Chemical Society. [939. pages 473 476, using Z-mercaptobenzonthiazole as a strating material. Synthesis Example 2 (Compounds [-9 through l-l7) The compounds can be synthesized according to the H C 5 m. p. 0 process described in the Journal of The Chemical Soci- C S ty. I949, pages 1.503 L509, by reacting dithiocarbamate with an alpha-haloketone. \N Compounds ll8-l-29 can be prepared by the proeedure of Synthesis Example I, in which the starting material is changed.

Compounds l30-l39 can be prepared by the procedure of Synthesis Example 2. in which the starting materials are changed.

Compounds |-l -l-39 are well known in the art.

As illustrative of the polyalkylene oxide derivatives used in the invention there are addition polymerization products between alkylene oxides such as ethylene oxide or propylene oxide and a compound such as water. an aliphatic alcohol. an aromatic alcohol. glycols. fatty acids. organic amines and a dehydrated compound of a hexitol derivative; condensates of a polyalkylene oxide with a compound such as just described: or block co-polymers of various alkylcne oxides such as ethylene oxidepropylene oxide block copolymers as described in US. Pat. No. 3.5lo.380 etc. Additional examples of such materials are described in. for example. US. Pat. Nos. 2.400.532; 3.294.537; and 3.294.540. French Pat. Nos. l.49l.805; 1.596.673. Japanese Patent Publication No. 23466/65. and the like.

The polyalkylene oxide derivatives used in the pres ent invention are those having a molecular weight of from 500 to 12.000. most preferably from 800 to 6.000. Specific examples thereof include the following:

nocs ca c tcn ca o) (1 11 wherein h represents an integer of 14 55 and (HT is an integer of4 210. Such materials are available from Wyandotte Chemical Co. under the trade name Pluronic L-44. L-ol. L-62. L-64. L68. L-8l. P-65. P-75. F-BS. etc. In Pluronic L68. for example. the molecular weight is 8.750. 12 32 and u+(=l59; in Pluronic P-75. the molecular weight is 4.l00. [F37 and u+c= l; and in Pluronic F-88. the molecular weight is I 1.250. h=4l and u+c=204.

d. HOCl-l CH O(CH CH- ,O) .,CH CH 0H (CH CH O H wherein 1+ m n about 20. and

aoca cn owa ca o) 421 11 The compounds used in the invention and represented by the general formula (I) are characterized by the presence of a thioketone functional group. It is important in the invention that compound (I) has a thioketone functional group and the substituent R be a substituent other than a hydrogen atom. Such a com pound gives effective results when combined with a polyalkylene oxide derivative. Since in these compounds R is not hydrogen the compounds cannot form a tautomeric isomer having a mercapto group. and no reduction in sensitivity is encountered upon the use of such compounds. On the contrary. these compounds supersensitive with most generally used simple merocyaninc dyes. dimcthine merocyanine dyes and carbocyanine dyes. and hence they raise the sensitivity without increasing the fog formation.

The silver halde photographic emulsions in accordance with the present invention can be spectrally sensitized. for example. by one or more sensitizing dyes represented by general formula (ll) or (III):

General formula II wherein Z. represents the atoms necessary to form a tctrazole nucleus. pyrrolidine nucleus. pyridine nu cleus. thiazole nucleus. thiazoline nucleus. selenazole nucleus. selenazoline nucleus. oxazole nucleus. oxazoline nucleus. indolenine nucleus or imidazole nucleus. L represents a methine chain. such as an unsubstituted or a substituted methine group. for example. an alkyl( C,C..)-substituted methine group or a phenylsubstituted methine group. Y represents an oxygen atom. sulfur atom or =NR.-, (wherein R represents an alkyl group having l 6 carbon atoms. c.g., methyl. ethyl. propyl. cyanoethyl. allyl. carboxycthyl. dimethylaminoethyl. benzyl group. etc.. an aryl group such a phenyl group or psulfophenyl group) n represents 0 or 1. R and R represent an alkyl group (e.g.. methyl. ethyl. carboxyethyl. carhoxybutyl. sulfoethyl. sulfopropyl. allyl, morpholinoethyl. acetoxypropyl. benzyl group. etc), aryl group such as a phenyl group. a tolyl group. a pyridyl group or like group.

General formula (Ill) Y A Y 2 e t 2 CCH=C-CH=C K U 3 dichlorobenzimidazole. 5-chloro-6-methylsulfonylbenzimidazole. or the atoms necessary to form an aromatic ring of the naphthalene series. such naphthothiazole. naphthoselenazole or naphthoimidazole. the terms benzene and naphthalene series thus including both unsubstituted or substituted benzene and naphthalene. for example. the substituent can be an alkyl group. generally a C,-C,;,. preferably a C -C.. alkyl group. a halogen atom or a phenyl group. Y and Y represent an oxygen atom. sulfur atom. selenium atom. or NR;(R; being a (C,-C alkyl group. preferably a C,-C,; alkyl group such as methyl. ethyl. allyl. acetoxyethyl. cyanoethyl group. etc.). R,-, and R represent an alkyl group having not more than 6 carbon atoms. such as methyl. ethyl. propenyl. hydroxyethyl. amidoethyl. carboxypropyl. sulfoethyl. 4-sulfobutyl. 2-[2-( 3-sulfopropoxy)ethoxy] ethyl. propylenesulfate group or a group as described in Zeitschrift fuer Wissenschaftliche Photographic" 63. I49 158. l969. written by E. J. Poppe. X represents an anion as is used in the synthesis of cyanine dyes. such as a bromine ion. iodide ion. p-toluenesulfonate anion. perchlorate anion. etc.. 1 represents 1 or 2. and. when an internal salt is formed. 1 represents 1.

Compounds represented by general formula II are described. for example. in French Pat. No. l.596.673. Specific examples thereof include the following compounds:

Compounds represented by General formula III can be prepared according to the procedures in US. Pat.

Nos. 2.503.776 and 3.l77.2l0. British Pat. No. 742.ll2 and German Pat. Nos. 1.072.765 and l.l63.67l.

The additive amounts of the compounds of General formulae II or III are same as those for the compounds of General formula S l s CH l5 l 3 o i =0 CH= N o N L I 5' 23 2 )N-CH3 H CH CH= f i d H36 I CAN /6 COOH 5 =cn- H2 -s CH=CH-CH= I (011 80 (c11 SO Na The silver halide emulsion used in the present invention can be silver chloride. silver bromide. silver iodide or a mixture thereof. In particular, silver chlorobromoiodide emulsions comprising silver chlorobromide and less than 2 mole percent of iodide ions are preferred. Furthermore. silver halide emulsions comprising grains whose mode size is less than 0.8 micron and which contain at least 50 mole percent chloride ions as grainforming ingredients are suitable. Usually the mode size is in the range (HM-0.8 microns. preferably 0.2-0.8 microns.

Preferred emulsions for use in the present invention have a silver halide grain size of 0. 1-1 micron. and contain 30-150 g per 1 mol of silver halide ofa hydrophilic collid material. The most preferred hydrophilic colloid material is gelatin. There are merely preferred embodiments. of course. and should not be construed as limiting the invention.

In the emulsion, one or more hydrophilic colloidal materials are used as a dispersingg agent. and the exact material selected is not overly critical. i.e.. materials such as gelatin. gelatin derivatives such as phthaloylated gelatin or malonylated gelatin. cellulose derivatives such as hydroxyethyl cellulose or carboxymethyl cellulose. soluble starches such as dextrin or alkalified starch. hydrophilic high molecular weight polymers such as polyvinyl alcohol. polyvinyl pyrrolidone. polyacrylamide or polystyrenesulfonic acid. and like materials may be used.

The emulsions can be chemically sensitized according to any process known to the art such as sulfur sensitization. reduction sensitization. sensitization with noble metal ions. e.g.. a gold compound. a platinum compound. etc.. or a combination of such processes. In addition. metal ions other than silver ions, such as group Vlll metal ions and group [I metal ions can be used to make the gradation more contrasty. to stabilize the emulsion. to control the formation of fog and to supersensitize the emulsion.

The emulsions can have added thereto a stabilizer (e.g.. a 4-hydroxy-l.3.3a-7-tetrazaindene derivative). an antifogging agent. a hardener. a surfactant. a hydrophilic synthetic polymer. a latex polymer and a dye for preventing irradiation. all of which materials are commonly used in the production of light-sensitive materials.

The compounds of general formula (I) used in the invention is preferably used at a level of from about It)" to about l0" moles per 1 mole of silver halide. The polyalkylene oxide derivative is preferably added in an amount of from about ().0l to l g per l mole of silver halide. Optimum results are achieved within these ranges.

In case of adding the compound to an adjacent layer such as an overcoat layer. a backing layer. an antihalation layer. an intermediate layer or a silver halide layer. the amount of the compound is based on the silver halide contained in the silver halide emulsion layer into which the compound is diffused from the adjacent layer.

The compound of general formula (I) and the polyalkylene oxide derivatives can be added by dissolving them in water. water-miscible alcohols (e.g.. methanol. ethanol. methyl cellosolve. etc.). or ketones (e.g.. acetone. etc. and then either directly added to the emulsion or added to an adjacent layer to form a multi-layer structure.

A completed emulsion in accordance with the present invention is applied to a suitable support such as a glass plate. cellulose acetate film. cellulose acetate butyrate film. polyester film or like plastic film. etc.. for use. While paper can be used. it is not used in commercial practice.

An antihalation layer or a filter layer may be provided on or under the emulsion layer in accordance with the invention.

The silver halide high-sensitive material obtained by the present invention may be processed in any conventionally known manner. In development there is used. for example. an infectious developer. Such infectious developer fundamentally comprises dihydroxybenzene (developing agent). alkali. a small amount of sulfite. and sulfite ion buffer.

The developing agent. dihydroxybenzene can be selected from those known in the field of photography. Specific examples thereof include hydroquinone. chlorohydroquinone. bromohydroquinone. isopropylhydroquinone. toluhydroquinone. methylhydroquinone. 2.3-dichlorohydroquinone. 2.S-dimethylhydroquinone. etc. Hydroquinone is particularly preferred. These developing agent may be used singly or as combinations thereof.

A sulfite ion buffer is used in sufficient amount to effectively maintain the sulfite level in the developer low. Illustrative of such materials are aldehyde-alkali hydrogen sulfite adducts such as a formalin-sodium hydrogen sulfite adduct. ketone-alkali hydrogen sulfite adducts such as acetone-sodium hydrogen sulfite adducts. carbonyl bisulfite-amine condensation products such as sodium bis( Z-hydroxyethyl )aminomethanesulfonate, and the like.

The developing agent. or agents. are used in amounts as are commonly used with prioir art infectious developers. e.g.. about 5 to about 50 g of developing agent or agents per 1 of developer. preferably l0 30 g per liter of developer.

The same can generally be said for the sulfite ion buffer. and such materials are generally used in an amount of from about l3 to about 130. preferably 30-60. g per liter of developer.

An alkali material is added so as to render the developer. alkaline. preferably to a pH above 9. The type of alkali is not limited. and any of those commonly used in the photographic arts can be used for this purpose. e.g.. carbonates such as potassium. sodium or calcium carbonate, etc. borax. and secondary or tertiary phosphates such as disodium phosphate. trisodium phos phate. etc.

The developer may further contain various additives known to those skilled in the art. such as an organic antifogging agent. cg. benzotriazole. l-phenyl-S- mercaptotetrazole. etc.. polyalkylene oxides. amine compounds. organic solvents. e.g.. triethylene glycol. dimethylformamide. methanol. ethylene glycol monoalkyl ether. etc.. and the like.

By using the light-sensitive material in accordance with the invention. there can be obtained high contrast gradation with good toe-gradation without the necessity of a comparatively long development as in the processing of conventional silver halide light-sensitive ma terial wherein a polyalkylene oxide derivative is used. In addition. there can be obtained the effect that the quality of individual dots is uniform.

The present invention will now be described in greater detail by reference to several non-limiting Examples.

EXAMPLE I A chemically ripened silver chlorobromoiodide gela tin emulsion l4 g gelatin/mole silver halide) was prepared in a conventional manner. i.e., by adding aqueous solutions of silver nitrate and potassium halide to an aqueous solution of gelatin. physically ripening it. and then adding a gold salt and sodium thiosulfate to the mixture. The bromide ion content and the iodide ion content in the emulsion were 17 mole percent and 0.2 mole percent. respectively. The amount of silver per 1 kg of the emulsion was about l.3 moles. and the mode size of the silver halide grains was 0.6 micron. 700 g portions of the resulting emulsion were weighed out in 20 pots. Each emulsion was prepared according to the prescription given in Table l. Preparation was as follows: first. each pot was heated to 45C with stirring;

l. the spectral sensitizing dye was added.

2. one compound selected from the group consisting of the compounds represented by general formula (I) was added. and

3. the polyalkylene oxide derivative was added.

Table l-Continued Compound Polyalkylene Sample sensitizing dye of general oxide No. formula (I) derivative ('om- Added Com- Added C om- Added amount pound ml pound amount pound amount (mole conml ml"'*" centration per ml. I

2x10 (2) do. (C I do. 20 (2) do. l l (C) do. do. 40 (2) do. l 2 (C) do. [-22 20 (2) do. l3 (C) dov do. 40 (.2) do. l4 (3) l2 (A) 50 (3) do.

(5Xl()"] l (1 (A) (10. 1-29 (3) do. I 7 (A) do. do (3) do. l8 (A) do. l l l 20 l) (A) do. l-Z 4U l do. 20 L2 40 l do.

In the above Table.

A. l-ethyl-lethyl-5-( 3-sulfopropyl-2- benzoxazoliniden)ethylidene-Z-thiohydatoin.

B. anydro-l l-ethyl-3 .3-bis(sulfopropyl)-naphtho- I l .2-dl-thiacarbocyanine hydroxide.

C. 9-methyl-3.3'-bis-(sulfobutyl)- selenacarbocyanine hydroxide.

l. polyethylene oxide derivative containing about ethylene oxide chains per oleylphenoxy group. molecular weight about 2,600.

2. polyethylene oxide derivative containing about 30 ethylene oxide chains per oleyl alcohol group. molecular weight about [.500.

3. polyalkylene oxide derivative of a block copolymer having a molecular weight of about 2.000 and comprising polypropylene oxide chains and polyethylene oxide chains. the number ratio of propylene oxide groups to ethylene oxide groups in the molecule being about 30 8,

4. ethylene oxide derivative containing about ethylene oxide chains per oleylphenoxy group. molecular weight about 3.500.

*Molar concentration and the amount of the methanol solution of the sensitizing dye added are shown.

**A methanol solution of 5 X 10* molar concentration per ml was used.

***0.5 percent by weight aqueous solution was used.

10 cc of a 1 percent aqueous solution of sodium dodecylbcnzenesulfonate and 10 cc of a 2 percent aqueous solution of the sodium salt of 6-hydroxy-2.4- dichloro-S-triazine were added to each of the thus obtained emulsions as coating aids. and the emulsion obtained then applied to cellulose triacetate film in a dry thickness of about 4 and then dried.

The coated film was cut into strips. and the resulting strips were wedge exposed using a 2.854K light source by means of a sensitometer for one section (250 lux). The exposed strips were developed with the use of the following developer as is commonly employed in the development of lithographic light-sensitive materials at 20C for 1.5 minutes. 3 minutes or 4 minutes. and then fixed.

Composition of the developer:

25 26 Water (hem 1 CC dot image having the following average density by Anh\drous sodium sullitc 30 g 7 Pum'fmnufldemue 75 g means of a micron densitometer having an aperture ../J. Sodium bisulfite 2.2 s width X 111 t, starting from the side of low density. Boric acid 7.5 g Hydroquinone 22.5 g Potassium bromide 1.6 g Water to make 1 liter. Averilgc D111 density quaht) FIG. 2. curve 11.41) D FIG. 3. cune 32 (1.311 The density of the strips thus processed was mea- Flo, 1 m- .11 0.411 a H0. 4. curve 41 (1.37 sured to obtain the characteristic cur es of the strips. FIG 4. Cum: 42 (U7 A The results are shown in Table 2.

Table 2 Relative sensitivity Contrast (7) Dot quality Remarks Developing time: 1.5 min. 3 min. 4 min. 1.5 min. 3 min. 4 min. 1.5 min. 3 min. 4 min. Sample 1 5.6 12.3 15.5 6 5" 5 C D D FIG. 2 2 1.8 3.1 3 13 D C C FIG. 3

Curve 32 3 5.2 6.3 8 12 D C C 4 1.4 9.1 15.1 8 9 13 C B B 5 2.4 13.8 27.6 10 13 8 B A C 6 2.6 19.0 31.6 10 10 10 B A A 7 6.0 18.6 36.4 11 13 6 B A B 8 1.8 4.0 10 13 D C B 9 1.5 3.1 4 13 D D D 10 1.5 10.0 17.4 7 13 13 D B B 1 1 2.4 14.8 28.1 12 8 8 B B B 12 3.8 10 7 13 D B B 13 1.6 12.6 28.2 13 6 7 D B B 14 1.3 2.5 7 13 D D B 15 8.5 31.6 56.4 13 13 7 D B B ""FIG. 1.

Curve 1 1 16 21.4 32.6 62.5 13 13' 10 A A 8 3FIG. 1.

Curve 12 t 7 8.0 30.0 40.0 13 13 13 A A A 18 7.9 10.5 14.5 13 13" 13 C B C FIG. 5.

Curve 41 19 20.9 48.0 89.0 13 13" 7 A A B F1G. 4.

Curve 42 20 3.5 9.5 18.7 13 9 6 A B B 7FIG. 3,

Curve 31 In the Table 2. the relative sensitivity is shown in Curve 51 i F|(; 5 shows h range f i di id l terms of the relative value of the reciprocal of the expocurves used to Obtain Curve 4] in FIG 4 and Curve 52 Sure amount Corresponding to the P m the Characin FIG. 5 shows the range with the curve in FIG. 4. 1t tcristic curve where the optical density IS 0.5. Contrast can b d t d th t th lit f th i di id l 15 indicated in ($11118 Of average SlOlp at the linear dots was made uniform by the presence of the ompart of the characteristic curve. means that the pound of the general formula (1) in accordance with value was too small to measure with accuracy, while th i v nti 13" means that the value 118 I00 arg I as Studying the results given in Table 2 in detail, it can with accuracy. though at least higher than 13. be seen that with the silver halide light sensitive mate- The rating of dot quality was determined by closely 5O rial containing neither the compound represented by placing a contact screen 1 133 line/l inch) on a sample general formula (I) nor the sensitizing dyes represented and exposing and developing the sample in the same by the general formula 11 or 111. i.e.. containing only a manner as above. and observing the thus obtained dot polyalkylene oxide derivative, there is the tendency image with an optical microscope. The samples were 55 that the longer the developing time the higher both the classified into four equally spaced grades, A (best). B. relative sensitivity and contrast become. and the more C and D. (worst-impractical for use) in the order of the improved the dot quality becomes (see Samples 2. 8 sharpness of their dot edges. and 14).

The results of this rating method approximately com- F rther in the case of adding the sensitizing dye repcided with the order of height of the edge grad nt 0 resented by general formula 11 or 111 and not adding the tained by measuring the micron density of the dot image by means of a micron densitometer.

1n FIGS. 2 4 curves showing the relationship between distance and optical density with respect to the edge portions are given. the relationship being based on the average of six dots.

These were obtained by measuring the density of a compound represented by general formula 1. as the developing time increased the sensitivity increased. However. in this case there was not great change in the contrast (sec Sample 3) and. in some cases, a detrimental effect was encountered (see Sample 9}. Although there were the cases wherein both sensitivity and contrast were good as in Samples 15 and 18. the dot quality can- 27 not be said to be improved in proportion to sensitivity and contrast.

However. it can be seen that by utilizing a system within the present invention there was obtained an ex- What is claimed is: l. A silver halide lightsensitive material which comprises in a silver halide emulsion layer or a layer adja Cent thereto at least one heterocyclic thioketone comcellent, high contrast light-sensitive material having 5 pound which does not form a mercapto group through higher sensitivity than that of any of the conventional tautnmerism, said compound being represented by the materials which provided good dot quality. (For examf ll i ggngrdl f l (I); ple. compare Sample 19 or 20 in accordance with the present invention with Sample 18. a comparison sam pl H) I Q\ I (I) EXAMPLE 2 A chemically ripened silver chlorobromide gelatin emulsion (74 g gelatin/mole silver halide) was prepared in a conventional manner as in Example 1. The brol5 R mide ion content in the emulsion was 30 mole percent, and the amount of silver per l kg of the emulsion was about l.l moles. wherein represents the group of atoms necessary to Samples of the light-sensitive material was prepared form a heterocyclic ring selected from the group conaccording to Example l under the conditions given in 20 sisting of benzothiazoline-Z-thione ring, ben- Table 3. and subjected to sensitometry as in Example zoselenazolin 2 thione ring, benzoxazolin-Lthione l. The results shown in Table 3 were obtained. ring, imidazolin-lthione ring, benzimidazolin-Z-thione The terms in Table 3 have the same meaning as in T21 ring. selenazolidin-2-thione ring. 4'selenazolin-2- bles l and 2. thione ring. l.3.4-thiodiazolin-2-thione ring. l,3.4-

Table 3 Com Poly- Amount pound of Amount alkylene (cc) Relative Contrast (y) Dot eneral (cc) oxide sensitivity quality ormula (Molar derivby No. (I) cone.) ative wt. l'30" 3' 4' l'3tl 3' 4' l'30" 3' 2l 6.0 I25 162 6 4 D 22 4 1.4 2.0 3.1 (i ll ll D B (0.5%) 23 ll9 IOU (2x10- 4 do. 24 12.6 24.0 13 13 7 B A 24 1-2 50 2x10 4 do. 1.9 8.0 15.9 10 13 8 B A 25 do. 100

2x10 4 do. 2.3 9.5 16.0 It) 13 8 B A 26 do. l50

2x10 4 do. 23 9.3 17.3 13 13 7 A A 27 1-39 50 (2X10 4 do. 3.6 l4.0 1.58 l3 ll 6 A B 28 do. I00

(2 l()'") 4 do. 27 12.1 18.8 13 8 6 A B 29 do. l50

(2Xl0"") 4 do. 3.0 H2 160 l3 7 6 A B 30 I-lS 100 (2Xl()") 4 do. 1.1 2.0 6.8 6 13 13 B B 31 do. I

(2x10) 4 dd. 1.6 2.4 7.1 7.1 13 13 B A From the results shown in Table 3 it can be seen that according to the present invention dots having good quality and high sensitivity can be obtained with a short development.

Preferred embodiments of the present invention are as follows.

1. In the invention, a silver halide emulsion spectrally sensitized with a sensitizing dye represented by the general formula (ll) or (Ill) is used.

2. In the invention, an emulsion containing silver halide grains ofless than 0.8 micron in grain mode size and comprising at least 50 mole percent silver chloride are used.

While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

selenadiaZolineQ-thione ring. l,2-dihydropyridin-2- thione ring. l.2dihydroquinolin-2-thione ring, 4,5- tetramethylenethiazolimZ-thione ring, 4,5- trimethylenethiazoline-2-thione ring, naphthothiazolin- 2-thione ring. and thiazolidin-Z-thione ring. and R represents an unsubstituted alkyl group, an aralkyl group an aryl group. a Z-pyridyl group or a dipyridyl group and at least 1 polyalkylene oxide derivative having a molecular weight ranging from 500 to H.000 selected from the group consisting of a. block copolymers of alkylene oxide.

b. polyalkyleneglycols.

c. addition polymerization products between alkylene oxides and a compound selected from the group consisting of an aliphatic alcohol, an aromatic alcohol. glycols, fatty acids. organic amines. and a dehydrated compound of hexitol derivatives. and

d. condensates ofa polyalk vlene oxide with said compound, the combination of said thioketone compound and said polyalkylenc oxide derivative being incorporated in said layer in concentrations which provide a high edge gradient with comparatively short development time and/or dots having good toe-gradation when said material is developed.

2. The silver halide light-sensitive material of claim I wherein the silver halide has a mode grain size of 0.2 to 0.8 microns.

3. The silver halide light-sensitive material of claim 1 wherein the silver halide emulsion layer comprises a hydrophilic colloid.

4. The silver halide lightsensitive material of claim I wherein the comound of general formula (I) is present in an amount of from about l() to about moles and the poly-alkylene oxide derivative is present in an amount of from about 0.01 to about 1 g per mole of silver halide in the silver halide emulsion layer.

5. The silver halilde light-sensitive material of claim 1 wherein R is an unsubstituted alkyl group of [-13 carbon atoms.

6. The silver halide light-sensitive material of claim 1 wherein R is an aryl group.

7. The silver halide light-sensitive material of claim 1 wherein R is a 2-pyridyl group or a dipyridyl group.

8. The silver halide light-sensitive material of claim I wherein R is selected from group consisting of a methyl group. ethyl group. propyl group. hexyl group. decyl group. and a benzyl group.

9. The silver halide light-sensitive material of claim 6 wherein R is selected from the group consisting of a phenyl group. Imethylphenyl group. 4-methoxyphenyl group and a 4-chlorophenyl group.

10. The silver halide light-sensitive material of claim 1 wherein the polyalkylene oxide derivative is selected wherein 11 represents an integer of 14-55 and n+0 is an integer of 4-210,

d. HOCH CH O(CH CH O) CH CH OH l 0-(CH CH O) H wherein 1+m+u about 20, and 

1. A SILVER HALIDE LIGHT-MATERIAL WHICH COMPRISES IN A SILVER HALIDE EMULSION LAYER OR A LAYER ADJACENT THERETO AT LEAST ONE HETEROCYCLIC THIOKETONE COMPOUND WHICH DOES NOT FORM A MERCAPTO GROUP THROUGH TAUTOMERISM, SAID COMPOUND BEING REPRESENTED BY THE FOLLOWING GENERAL FORMULA (1): R-N<(-C(=S)-Q-) WHEREIN Q REPRESENTS THE GROUP OF ATOMS NECESSARY TO FORM A HETROCYCLIC RING SELECTED FROM THE GROUP CONSISTING BENZOTHIAZLOINE-2-THIONE RING, BENZOSELENAZOLIN-2-THIONE RING, BENZOXAZOLIN-2-THIONE RING, IMIDAZOLIN-2-THIONE RING, BENZIMIDAZOLIN-2-THIONE RING, SELENAZOLIDIN-2-THIONE RING, 4 SELENAZOLIN-2-THIONE RING, 1,3,4-THIODIAZOLIN-2-THIONE RING 1,3,4-SELENADIAZOLINE-2-THIONE RING, 1,2-DIHYDROPYRIDIN-2THIONE RING, 1,2-DIHYDROQUINOLIN-2-THIONE RING, 4,5-TETRAMETHYLENETHIAZOLIN-2-THIONE RING, 4,5-TRIMETHYLENETHIAZOLINE-2THIONE RING, NAPHTHOTHIAZOLIN-2-THIONE RING, AND THIAZOLIDIN-2THOINE RING, AND R REPRSENTS AN UNSUBTITUTED ALKYL GROUP, AN ARALKYL GROUP AN ARYL GROUP, A 2-PYRIDYL GROUP OR A DIPRIDYL GROUP AND AT LEAST 1 POLYAKYLENE OXIDE DERIVATIVE HAVING A MOLECULAR WEIGHT RANGING FROM 500 TO 12,000 SELECTED FROM THE GROUP CONSISTING OF A. BLOCK COPOLYMERS OF ALKYLENE OXIDE, B. POLYALKYLENEGYLCOLS, C. ADDITION POLYMERIZATION PRODUCTS BETWEEN ALKYLENE OXIDES AND A COMPOUND SELECTED FROM THE GROUP CONSISTING OF AN ALIPHATIWC ALCOHOL, AND AROMATIC ALCOHOL, GYCOLS, FATTY ACIDS, ORGANIC AMINES, AND A DEHYDRATED COMPOUND OF HEXITOL DERIVATEVES, AND D. CONDENSATES OF A POLYALKYLENE OXIDE WITH SAID COMPOUND, THE COMBINATION OF SAID THIOKETONE COMPOUND AND SAID POLYALKYLENE OXIDE DERIVATIVE BEING INCORPORATED IN SAID LAYER IN CONCENTRATIONS WHICH PROVIDE A HIGH EDGE GRADIENT WITH COMPARATIVELY SHORT DEVELOPMENT TIME AND/OR DOTS HAVING GOOD TOE-GRADATION WHEN SAID MATERIAL IS DEVELOPED
 2. The silver halide light-sensitive material of claim 1 wherein the silver halide has a mode grain size of 0.2 to 0.8 microns.
 3. The silver halide light-sensitive material of claim 1 wherein the silver halide emulsion layer comprises a hydrophilic colloid.
 4. The silver halide light-sensitive material of claim 1 wherein the comound of general formula (I) is present in an amount of from about 10 6 to about 10 3 moles and the polyalkylene oxide derivative is present in an amount of from about 0.01 to about 1 g per mole of silver halide in the silver halide emulsion layer.
 5. The silver halilde light-sensitive material of claim 1 wherein R is an unsubstituted alkyl group of 1-13 carbon atoms.
 6. The silver halide light-sensitive material of claim 1 wherein R is an aryl group.
 7. The silver halide light-sensitive material of claim 1 wherein R is a 2-pyridyl group or a dipyridyl group.
 8. The silver halide light-sensitive material of claim 1 wherein R is selected from group consisting of a methyl group, ethyl group, propyl group, hexyl group, decyl group, and a benzyl group.
 9. The silver halide light-sensitive material of claim 6 wherein R is selected from the group consisting of a phenyl group, 2-methylphenyl group, 4-methoxyphenyl group and a 4-chlorophenyl group.
 10. The silver halide light-sensitive material of claim 1 wherein the polyalkylene oxide derivative is selected from the group consisting of a. 